Sulfurous acid is a corrosive sulfur oxoacid and a tautomer of sulfonic acid. As pure, anhydrous sulfurous acid cannot be isolated, aqueous solutions of sulfur dioxide are often referred to as sulfurous acid and are used as reducing agents and disinfectants.
Sulfurous acid is used as a reducing agent, bleaching agent and disinfectant. It is utilized for bleaching of moistened wool, straw for hats, and other materials injured by chlorine. It finds application as a disinfectant as well as used externally for its parasiticidal effect in various skin...